ML20235D097

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Safety Evaluation Supporting Util 660531 Proposal to Const & Operate Single Cycle BWR of 2,255 Mwt
ML20235D097
Person / Time
Site: Quad Cities, 05000000
Issue date: 12/30/1966
From:
US ATOMIC ENERGY COMMISSION (AEC)
To:
Shared Package
ML20235B311 List: ... further results
References
FOIA-87-111 NUDOCS 8709250116
Download: ML20235D097 (22)


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DEc 3 01968

- ,;gagy 90CE M COPY SAFETY EVALUA'"ICN BY THE l DIVISION OF REACTOR LICENSING l

U.S. ATG4IC ENERGY COMMISSION IN THE MATTER OF COMMotMEALTH EDISON COMPANY ]

QUAD-CITIES STATION UNITS 1 AND 2 CORDOVA, ILLINOIS D00lTT !!OS, JiD 50-265 U

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TABLE OF CONTENTS I. Introduction .......................... 1

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II. Site- .............................. 4' ,

-i III. Pleat Features Which Differ From Dresden Units 2 and 3 ..... 8-

. IV. Ehgineered Safeguards Systems . . . . . . . . . . . . . . . . . ' . . 22 V. : Accident Analysis . . . . . . . . . . . . . . . . . . . . . . . . 15 VI. Report to the Advisory Committee cn Reactor Safeguards ..... 17-VII. Conclusions . . . . . . . . . .' . . . . . . . . . . . . . . . . . 18 Appendix A: ACRS Letter to Chairman, AEC, dated

. December, 14, 1966 Appendix B: Report to the AEC Regulatory Staff, U. S. Weather Bureau AppeM ix C: Report to the M:C Rer,tlatory Staff, U. S. Geological Survey Appendix D: Report to the AEC Regulatory Staff, U. S. Coast and Geodetic Survey Appendix E: Report to the AEC Regulatory Staff,  !

Nathan M. Newmark, Consulting Engineering Services Appendix F: Report to the AEC Regulatory Staff, U; S. Fish and Wildlife Service Appendix G: Safety Evaluation by the Division of 1

, Reactor Licensing, AEC, In the Matter of Commonwealth Edison Company, Dresden Nuclear Power Station Unit 3 l

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I. Introduction The Commonwealth Edison Company submitted an application dated May 31, 1966, to the Atomic Energy Connission for licenses to construct and operate a single cycle boiling water reactor of 2255 Mit, supplied by. General Electric, to bo Unit 1 at its Quad-Cities site near Cordova, T111nois. The application was amended to include an identical Unit 2 by Amendment No.1, dated August 18, 1966.

This report is an evaluation of both proposed units and is based on the Plant Design and Analysis Report and four amendments thereto. The issues to be con-sidered, and on which findings must be made by an atomic safety and licensing board before the license requested may be issued, are set forth in the Notice of Hearing issued by the Commission and published in the Federal Register on December 20, 1966.

The Quad-Cities units are substantially similst to Dresden Units 2 and 3 which have recently been considered by an atomic safety and licensing board and for which provisional construction permits have been issued. Cennonwealth Ediscn Company is the applicant in both instances. Accordingly, in response to the Commission's desire to shorten and simplify the hearing and decisional precess, this repert deals only with those features of the proposed Quad-Cities staticn which differ from the Dresden Units 2 and 3 or abcut which additional information has been submitted. The safety evaluation for Dresden Unit 3, dated August 31, 1966, is attached to this report (Appendix "G") for background information.

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.f In the course of our review of the application, we have' held a number of meetings with the' applicant and the plant designer, the General Electric -!

Company, .to discuss the preposed plant and to clarify the technical material submitted. In addition, the Advisory Comittee on Reactor Safeguards (ACRS) has.

also considered the application and has met and discussed it with us and the applicant. 7be matters discussed at each of these meetings and the~ principal - j correspondence following the initial May 31, 1966, submittal are summarized.

below. .

(1) July 20,1966 -- Representatives of the applicant and the regulatory staff discussed the application for Unit 1.

(2) August 18, 1966 -- Amendment No.1 to the application, consisting of replacement pages to the-report, was submitted to include an identical Unit 2 in the application.

(3) August 214, 1966 -- Additional information on many plant and site features was requested of the applicant. The information was provided-in Amendment No. 2, dated September 9,1966.

(4) September 15, 1966 -- Representatives of the applicant and the staff met to discuss the information submitted in Amendments No.1 and No. 2.

(5) September 16, 1966 -- A subcocunittee of the ACRS met with the applicant and regulatory staff to review the design and safety features of the proposed Units 1 and 2. The meeting included a visit to the proposed site.

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1 (6) October 12, 1966 -- Additicnal information was requested on certain shared features of Units 1 and 2 and on information submitted in Amendment No. 2. This infomation was supplied by Amendment No. 3, ,

1 dated October 18, 1966. I (7) November 16, 1966 -- Representatives of the applicant and the staff met to discuss material sub'mitted in Amendment No. 3.

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(8) November 17, 1966 -- A subcommittee of the ACRS met with the applicant to discuss the material in. Amendment No. 3.

(9)' November 28, 1966 -- Amendment No. 4 was submitted by the applicant to provide further desi6n detail on engineered safeguards systems.

The infomation is also applicable to the Dresden systems in response to the ACRS request in its letter on Dresden Unit 3, dated August 16, 1966.

(10) December 8,1966 -- Representatives of the applicant met with the ,

staff to discuss information on the safeguards systems submitted in Amendment No. 4.

(11) December 9,1966 -- The ACRS met with the applicant and the regulatory staff to review the proposed plant design. Following this meeting, the ACRS reported its views to the. Commission by letter dated December 14, 1966. A copy of the ACRS report is attached as Appendix "A".

The review and evaluation of tte proposed design and construction plans of the applicant at the construction permit stage of the proposed project is the

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l, (6). October 12, 1966 -- Additional fiiformation was requested on certain shared features of Ubits 1 and 2 and on information submitted in Amendment No. 2. This information was supplied by Amendment No. 3, .

dated October 18, 1966.

(7) November 16, 1966 -- Representatives of the applicant and .the staff met to discuss material sub'mitted in Amendment No. 3.

(8) November 17, 1966 -- A subcommittee of the ACRS met with the applicant to discuss the material in. Amendment No. 3.

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.(9) November 28, 1966 -- Amendment No. 4 was submitted by the applicant to provide further design detail on engineered safeguards systems.

The information is also applicable to the Dresden systems in response to the ACRS request in its letter on Dresden Unit 3, dated August 16, i 1966.

(10) December 8,1966 -- Representatives of the applicant met with the .

staff to discuss information on the safeguards systems submitted in -

. Amendment No. 4. j i

(11) December 9,1966 -- The ACRS met with the applicant and the regulatory l l

staff to review the proposed plant design. Following this meeting, l the ACRS reported its views to the. Commission by letter dated December 14, 1966. A copy of the ACRS report is attached as l Appendix "A".

The review and evaluation of the proposed design and construction plans of the applicant at the construction permit stage of the proposed project is the ,

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first stage of a continuing review of the design, ccustruction and operating i

features of this facility which will continue throughout the lifetime of the facility. Prior to issuing an operating iicense for the facility, we and the i

ACRS will thoroughly review the final design to determine that an of the Com-  !

mission's safety requirements have been met. The facility would then be operated only in accordance with the terms of an operating license and the Commission's regulations and under the continued scrutiny of the Commission's regulatory staff.  ;

, II. Site A. Description '

i The site of the proposed Quad-Cities plant consists of 488 acres in Roch  !

Island County, Illinois, on the east bank of the Mississippi River, approximate 3y three miles north of Cordova, Illinois. It is about 20 miles northeast of the Quad-Cities area (Davenport, Iowa; Rock Island, Moline, and East Moline, Illinois).

The distance frca the plant to the nearest site boundary 1.1 1,190 feet to the north. The distance to the nearest residence is 1,550 feet to the north. There are 15 river-front houses within one mile of the reactors. The nearest town is  ;

Cordova (1960 population, 502), .approximately 3 miles south of the site. The nearest city is Clinton, Iowa (1960 population, 33,589). It is approximately 5 miles to the city limits of Clinten and 10 miles to the center of the city.

The tots 1 population within 5 miles in 1965 was 5,369, and this is expected to )

increace to approximately 10,500 by 1980 Based on this information, the l l

population center distance is 5 miles and the low-population distance is about 4 miles.

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5-At our request, several consultants have commented on the proposed _ sit'e, ,

and their reports are attached as listed below.

Ccnsultant Subject Appendix U. S. Weather Bureau Meteorology "B" U. S. Geological Survey Geology and }{ydrology "C "

U. S. Coast and Geodetic Survey Seismology "D" Nathan M. Newmark Seismic Design "E" U. S. Fish and Wildlife Service Environmental Monitoring "F" B. Meteorology i

The appif. cant has presented data on the climatology and meteorology of the l site from Moline, Illinois, with supplementary data from a number of other cities ,

1 in the state. The Weather Bureau has stated that they expect the atmospheric  !

. diffusion at this site to be typical 'of the central portion of the country'which j is characterized by frequent nocturnal inversions and good daytime ventilation.

Since the proposed site is in an area of relatively high tornado frequency, components which are required for safe shutdown of the plant will be located either under the protection of reinforced concrete or located underground. Seismic design i considerations bring the strength of the concrete reactor building walls.to a level ruch that they could resist vinds of 400 mph within normal allowable stresses, J l

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e and would not fail until a speed.of approximately 600 mph is reached. In additim, !

independence of vital systems has been provided in the design to insure that a safe shutdown of the plant can be accomplished even if a tornadewgenerated missile were to penetrate the seccndary ecntainment. We believe that these design ,

considerations provide reasonable insurance that a tornado striking the propoded ,

plant would not result in a nuclear hazard. (Amendment 2, B-1; Amendment 3,1 9 1) 1 C. Geology and Hydrology All major structures will be supported on delomite bedrock. The information ^

submitiied indicates that the geologic and hydrologic conditions at the site present ,

no unusual decign or construction problems. There is no evidence of major faulting in the area, and it is estimated that major tectonic deformation has not occurred in some 60 million years. .

With reference to flooding, the finished grade elevation at the site vill be 594.5 feet. The normal pool elevation of the river, when flow is being controlled by the dams, is 572 f eet, and the maximum flood elevation during 92 years of y i

record was 586 feet. The 1000 year flood level is estimated,' by the applicant, to be 589.6 feet whichc,is still some 5 feet below site grade. Thus, it is con- ,

j cluded that flooding of the site is not a problem, l i

Since the Quad-Cities take their water supply from the Mississippi, begirming at a point approximately 15 miles below the site, the applicant has considered I

the consequences of an accidental release of liquid eft.: cent. Under the most adverse ccnditions rehtive to dilution in the river and assumed effluent release, it may be desirable for one or more of t'r citirsto shut off its water intake for a short l

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period while the peak effluent' concentration passes. We understand that for each city there is sufficient storage capacity to allow this action.

D. Seismology l The applicant has proposed to design the plant for a maximum ground accelera-t

" tion of 0.12g. In addition, the plant will be designed such that there vill be 4

no impairment of function of critical structures and components, and a safe and orderly shutdown vill be assured for a ground acceleration of 0.24g. Based on the report of the U. S. Coast and Geodetic Survey on the seismicity aspects of the site, we believe these proposed desi6n acceleraticus are adequate. In addition, our

,7 consultant, Nathan <M. Newmark, ins reported favorably on the ability of the proposed '

/l design to meet the above criteria.

E. Environmental Monitoring The applicant plans to cceduct a study of environmental radiation levels to t egin 2 yet.rs befctre the plant is sbarted up. Although detailed plans have not been formulated, the program will incluie air samples on site, water samples from the river and nearby wells, and samples of soil, vegetaticn, and milk frcan the surrounding are% The Fish and Wildlife Service has recommended monitoring of f river sediments and river life present in the area. We believe that these g

should ber included in the preoperationai survey. With this addition, the l

scope of the program is adequate.

In summary, we have found no feature of the site which would adversely affect the safety of the proposed plant, and we believe that important features of the site are adequately considered in the plant design and analysis.

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I III. plant Features Which Differ From Dresden Units 2 and 3 The design features of the Quad-Cities station which are different from, Dresden Units 2 and 3 are discussed below. In each case, the applicant has provided an analysis which indicates that the new features will not adversely influence the safety of the station. We agree that these systems will not degrade station safety. In all other respects, the proposed station is identical to Dresden Units 2 and 3 and the material presented in our safety analysis for Dresden Unit 3 applies equally to the Quad-Cities station.

A. Reactor Core Isolation Cooling (RCIC) System For the proposed Quad-Cities station design, a Reactor Core Isolation Cooling (RCIC) system replaces the Isolation Condenser system approved for Dresden Units 2 and 3. The primary purpose of the RCIC and Isolation Condenser systems is to supply cooling for the reacter core in the event of a turbine trip accccpanied by loss of a.c. power which would result in a loss of feedwater to the primary system. (Section X 4; Amendment 2, F-1 to F-6)

The RCIC system consists of a steam turbine which drives a centrifugal pump to supply about 350 gpm of makeup water to the reactor vessel. Steam for the RCIC turbine is supplied from the reactor via the primary system relief valves.

Excess steam is condensed in the suppression pool. This system is similar to, but of a smaller capacity than, the High Pressure Coolant In,jection (HICI) system proposed for the core cooling complex of both the Quad-Cities station and Dresden Units 2 end 3.

Fonowing isolation of the reactor from the normal heat sinks, the primary

  • system pressure increases, and a reactor scram is initiated at approximately 1050 psi.

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l 9-At approximately 1080 psi, the pressure relief valves open and relieve to the suppression pool. Normally, coolant makeup under these circumstances is em-densate supplied from the ccndensate storage tank by the feedwater pumps. In the event that feedwater is unavailable, either through depletion of the con-densate supply or loss o.! a.c. power, the steam supply line to the RCIC system would open automatica1]y on low reactor water level (by a d.c. operated valve).

Pumps driven by the RCIC turbine would then supply makeup water to the reactor vessel from the condensate storage tank. Sufficient condensate will be available at a minimum to permit continuous operation of the RCIC system for more than eight hours. In the event that the condensate source were unavailable, water frca the suppression pool could be used as an alternate source. Operation of the RCIC system would cause a slow heating of the suppression pool which can be controlled by the suppression pool cooling system.

Fission products entrained in the steam which is condensed in the suppression pool are not expected to result in radioactivity levels which would prevent inspection and maintenance of the suppression pool. Cleanup of the suppressica pool water can be acecmplished, if neccesary, by naking a pipe connection to the waste water filter and demineralized system.

Testing of the RCIC system will be possible at any time the primary system is pressurized and steam is available, m keup water under test conditions will be directed through a bypass line into the main condenser.

Based on our review of the proposed design cf the RCIC system, and on a program of regularly scheduled tests when the facility is operational, we believe i

the RCIC system as proposed wf11 provide ise?ation cooling equivalent in reliability to those systems proposed for previous facilities.

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,.~ B. Powdex Demineralized System The quad-Cities station liquid radioactive vaste disposal system will utilize Powdex non-regenerative demineralized units which, after approximately

.17 days of operation, will be back-flushed and the resin disposed as solid waste; The Powdex units will increase the cleanup capability of the system and discharge into the river will be reduced by about a factor of 20 over the regenerative system proposed for Dresden Units 2 and 3. We believe ttat the amount of radioactivity whibh might be accidentally released is significantly decreased by the use of this

- system and that its use in the facility is acceptable. (SectionVII-3; Amendment I

2,H-2) l C. Reactor Shutdown Cooling System The shutdown cooling system will circulate water frcm the primary system, under low pressure conditions, through either of two heat exchangers to remove decay heat. The system will have only one intake from the recirculation lines, but primary water can be returned through either of the recirculation lines.

The rating of each heat exchanger is about 0.8% of full power and either loop is j thus sufficient in capacity to provide shutdown cooling about two hours after the f reactor hac been scrammed from full power.

The heat exchangers are shared with the Im Pressure Coolant Injection (IJCI) l l Ccutainment Spray heat exchangers. Sharing of system components with an engineered safeguard system requires that the normal and emergency functions be isolable.

In this case, the normal function, shutdown cooling, is needed only when the 1

l reactor is shutdown and cool and depressurized, and the emergency l l l

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  • coolant injection vould not be required. Likewise,:the emergency function is needed only when the plant is in operation and the shutdown cooling function is .

not needed. In this respect, we believe that the normal' and emergency functions are isolable. We believe that proper attention has been given to the subject of single valve failure and the ' isolation of functico can be assured, and sharing of components of this system with an engineered safeguard system is acceptable.

(Section X-3; Amendment 2, D-5, G-3)

D. Spent Fuel Pools The spent fuel pools of the Quad-Cities station will be adjacent and will be connected by a transfer canal, a design feature not included in Dresden Units 2 and 3. The interconnected fuel pools will permit the transfer of refueling tools between the storage pools and will facilitate improved fuel cycles involving the alternate irradiation of fuel elements in the two cores. It is our understanding, however, that fresh fuel will be used for the initial startups for both reactors.

We can see no safety problem with the proposed sharing of pools and will consider alternate irradiation when proposed by the applicant. (SectionX-1; Amendment 3, 1-3) i E. Electrical System The output of the Quad-Cities station is delivered to the 345 KV switchyard which feeds four 345 KV transmission lines and the plant auxiliary power trans-formers. One of these lines runs in a westerly direction to the Hills Substation.

Two lines extend to the east on separate rights-of-way, and connect to a substation j 1

near Rock Falls. The fourth line runs to Barstow and shares a common set of ]

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towers with the line to Rock Falls to a point about one and one-half miles east I of the station. Startup power and the normal auxiliary power are obtained through transformers supplied from the 34 KV svitebyard.

We believe that the multiple system described above constitutes a reliable off-site power source. In addition, three diesel generators are sized such that any two can supply those safeguards which would be required after a coolant-locs I

accident in one unit and simultaneously supply vital normal shutdown systems I

for the second unit without reliance on off-site power.

F. Core Spray System A core spray complex has been proposed for the Quad-Cities station that has less redundancy than that proposed for Dresden Unit 3. Subsequent to the initial Dresden Unit 3 proposal, (2 loops, each with 200% capacity), a core floodir.g cystem was propeced and the need for the extra capacity of the core spray systems has since been reviewed. As a cecsequence the Quad-Cities proposal is for two loops, each with 100% capacity. We believe that this is adequate when combined with the backup capability of the Low Pressure Coolant Injection (flooding) system.

The foregoing represents the principal differences between Dresden Units 2 ,

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and 3 and the proposed Quad-Citie s station. In each case we conclude that the new design feature will not adversely affect plant safety.

IV. Engineered Safeguards Systems A. Core Cooling Systems The emergency systems proposed for the Quad-Cities station are the came in concept as those proposed for the Dresden Unit 3 reactor. In case of inventory 1

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-U- j loss from the primary system, a min 4="= of two heat removal systems of indepen-dent and different, principles are provided to dissipate core decay heat in . order to prevent fuel clad melting. The abnormal conditions ccmsidered are the loss of coolant due to a primary system rupture up to and including a double-ended severance of the largest primary system pipe coincident with a loss of nomal auxiliary a.c. power. (Amendment 2, G-5; Amendment 4)

Further design information on these systems has been provided in the present application and we have continued our review of the information now avail-able. Our comments on the proposed systees are as follows:  %

1. Since the ecndensate storage tank is the primary water source for the High Pressure Coolant Injection (HPCI) system we believe that it should meet Class I standards from a seismic design standpoint. We understand that the Quad-Cities station ccadensate storage tank will meet this criterion.
2. It may be desirable to provide redundant valving at each location in i the Low Pressure Coolant Injection (LPCI) system and HICI system where a single closed valve must open to allow operation of the system. We are continuing to study the necessity of adding this redundancy.  !
3. The instrumentation and DC power source for the HICI and Automatic Depressurization sytem should be designed such that no single failure would preclude operation of either of these systems. We understand that the Quad-Cities staticn system is being designed with this criterion in mind.

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B. Containment Cooling The LPCI system and the drywell spray system use the same pumps and heat exchanger. The drywell can be cooled, if necessary, by a spray by diverting flow from the LICI system to spray headers located in the drywell. The appli-

-1 cant's analysis has shown that such cooling would be required only if both the LPCI and Core Spray systems failed to prevent core heatup and a resultant metal-water reaction. Under these circumstances operation of containment spray would be required to cool non-condensible gases in the drywell.

The full capacity of the LICI system is required only for about three minutes, until the core is flooded. Subsequently, the LPCI system pumps would provide both containment spray and additional water to the core to make up for boiloff and leakage from the core shroud. During the first three minutes cen-tainment spray is not required.

We believe that as a minimum the proposed shared systems should include:

(1) provisions to operate the containment spray in parallel with the makeup requirement of the LPCI system, and (2) provisions to operate the containment spray at any time after the initial flooding function irrespective of the water level in the reactor.

We understand that the applicant's design will include these features.

The General Electric Company is in the process of developing final design and analysis of the core cooling and containment cooling functions. We believe that the information supplied to date is consistent with the objective of providing I

. safe, well-designed systems for these functions.

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V. Accident Analysis Our evaluation of major accidenta in the Quad-Cities Units 1 and 2 indicates

! that the ecnsequences of a significant accident in one unit would not be 1

l propagated to the unaffected unit to cause seccndary accidents. 'Ibe worst influence on the operation of the second unit would be the restriction of access for routine maintenance in the common secondary containment. Accordingly, the following discussion is limited to ccusiderations of fission product release from a single typical unit.

The four major accidents postulated by the applicant (those involving the potential release of significant amounts of fission products) explore four possible routes by which fission products might escape from the containment.

The control rod-drop accident releases fission products from the fuel within the confines of the primary coolant system. The refueling (fuel drop) accident releases fission products from the fuel directly to the secondary containment.

The steam line break accident releases fission products entrained in the primary coolant directly to the atmosphere. The coolant-loss accident releases fission products from the fuel to the pressure-suppression (primary) containment.

Our calculations of off-site consequences of these accidents are similar to those performed for Dresden Unit 3. Except for the steam line break accident, the lower exclusion distance, 0.225 miles, as opposed to 0.5 miles in the Dresden case leads to an increase of about 20% in the potential two-hour doses at the exclusion boundary. For the assumed steam line break accident (ground

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i release) potential doses at the exclusion boundary would be increased by a factor of 4. The 4-mile .'ow population distance at the Quad-Cities site, as opposed to the 10-mile low population distance at the Dresden site leads to calculated potential doses for the course.of the accident which are about 40%

higher for the Quad-Cities reactors. Nevertheless, all calcuhted doses remained well within Part 100 guidelines. A discussion of the assumptions for each j major accident is included in the Dresden Unit 3 Safety Evaluation.

A different mechanism has been postulated by the applicent for purposes of illustrating a fission product release directly to the secondary containment.

In previous applications, a fuel bundle dropped into an array made just critical by the withdrawal of two adjacent control rods was postulated to occur through a series of operator errors and procedural interlocks. In the Quad-Cities application, the mode of fission product release is physical damage (releasing gap fission products) occasioned by the drop of a fuel element into the core but assuming that a critical ecnfiguration does not occur. For this case our calculations indicate that fission products released from the area that could 1

be damaged by the drop of a fuel bundle would be well within 10 CFR Part 100 guidelines after release through the standby gas treatment system and the' stack.

We agree with the applicant that a refueling interlock system can be designed such that no single component failure, even when combined with operator errors, could lead to the drop of a fuel bundle into a critical fuel array.

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l lt VI. Report of the Advisory Committee on Reactor Safeguards f During its eightieth meeting, the Advisory Committee on Reactor Safeguards (ACRS) met with representatives of the applicant to review the proposed Quad-Cities' station. Previous to this a subcommittee of the ACRS had met with the applicant on September 16, 1966, and November 17,1966. A copy of the ACRS

, letter to the Commission concerning the Commonwealth Edison Company's applica-tion for a construction permit for the Quad-Cities Units 1 and 2 is attached as Appendix "A".

In this letter of December 14, 1966, the ACRS made recommendations on (1) engineered safeguards systems, (2) pressure vessel inspection during fabrica-tion and operation, and (3) the testing of steam line isolation valves. We intend to implement these recommendations as well as the recommmdations made by the ACRS in the Dresden Unit 3 letter of August 16, 1966. In particular, the details of design, fabrication procedures, plans for inservice inspection of the core cooling systems and analyses pertaining to these systems will be reviewed as the information beccanes available and ac similar General Electric designed i reactors are reviewed.  ;

The ACRS letter concluded:

. "The Advisory Committee on Raactor Safeguards believes that the various matters mentioned can be resolved during construction  !

and that the proposed reactors can be constructed at the Quad-Cities site with reasonable assurance that they can be operated I

without unaue risk to the health and safety of the public."

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VII. Conclusions ,

Based on the proposed design of the Quad-Cities Units 1 and 2,on the.

criteria, on the principles and design arrangements for systems and centnonents thus far described, which includes all of the important items, en the calculated potential emsequences of routine and accidental release of radioactive materials l

to the environs, on the scope of the development program which will be conducted, and on the technical competence of the applicant and the principal contractor which will design and cmstruct the, plant, we have concluded that, in accordance withtheprovisionsofparagraph50.35(a),10CFR50:

1. (a) ' The applicant has described the proposed design of the facilities, including, but not limited to, the principal architectural and engineering criteria for the design, and has identified the major features or componente incorporated therein for the protection of the health and safety of the public; (b) Such further technical or design information as may be required to complete the safety analysis and which can reasonably be left for later consideration, will be supplied in the final safety analysis report; (c) Safety features or components, if any, which require research and development have been described by the applicant and the applicant has identified, and there vill be conducted, a research and development program

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i reasonably designed to resolve any safety questions is l

associated with such features er compments; and j i

(d) On the basis of the foregoing, there is reasonable I

assurance that (i) such safety questions will be' '

satisfactorily resolved at or before the latest

'.date stated in the application for completion of cmstruction of the proposed facilities and (ii) taking j into consideration the site criteria contained in 10 CPR Part 100,' the proposed facilities can be constructed without, undue risk to the health and safety of the public;

2. The applicant is technically qualified to design and construct the preposed facility; and
3. The issuance of permits for the construction of the facilities will not be inimical to the comen defense and security or to the health and safety of the public.

In summary, we have concluded that there is reasonable assurance that the Quad-Cities Units 1 and 2 can be constructed and operated at the proposed site without endangering the health and sefety of the public.

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